1 /* 2 * Copyright (C) 1991, 1992 Linus Torvalds 3 * Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs 4 * Copyright (C) 2009 Matt Fleming 5 * Copyright (C) 2002 - 2012 Paul Mundt 6 * 7 * This file is subject to the terms and conditions of the GNU General Public 8 * License. See the file "COPYING" in the main directory of this archive 9 * for more details. 10 */ 11 #include <linux/kallsyms.h> 12 #include <linux/ftrace.h> 13 #include <linux/debug_locks.h> 14 #include <linux/sched/debug.h> 15 #include <linux/sched/task_stack.h> 16 #include <linux/kdebug.h> 17 #include <linux/export.h> 18 #include <linux/uaccess.h> 19 #include <asm/unwinder.h> 20 #include <asm/stacktrace.h> 21 22 void dump_mem(const char *str, unsigned long bottom, unsigned long top) 23 { 24 unsigned long p; 25 int i; 26 27 printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top); 28 29 for (p = bottom & ~31; p < top; ) { 30 printk("%04lx: ", p & 0xffff); 31 32 for (i = 0; i < 8; i++, p += 4) { 33 unsigned int val; 34 35 if (p < bottom || p >= top) 36 printk(" "); 37 else { 38 if (__get_user(val, (unsigned int __user *)p)) { 39 printk("\n"); 40 return; 41 } 42 printk("%08x ", val); 43 } 44 } 45 printk("\n"); 46 } 47 } 48 49 void printk_address(unsigned long address, int reliable) 50 { 51 printk(" [<%p>] %s%pS\n", (void *) address, 52 reliable ? "" : "? ", (void *) address); 53 } 54 55 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 56 static void 57 print_ftrace_graph_addr(unsigned long addr, void *data, 58 const struct stacktrace_ops *ops, 59 struct thread_info *tinfo, int *graph) 60 { 61 struct task_struct *task = tinfo->task; 62 unsigned long ret_addr; 63 int index = task->curr_ret_stack; 64 65 if (addr != (unsigned long)return_to_handler) 66 return; 67 68 if (!task->ret_stack || index < *graph) 69 return; 70 71 index -= *graph; 72 ret_addr = task->ret_stack[index].ret; 73 74 ops->address(data, ret_addr, 1); 75 76 (*graph)++; 77 } 78 #else 79 static inline void 80 print_ftrace_graph_addr(unsigned long addr, void *data, 81 const struct stacktrace_ops *ops, 82 struct thread_info *tinfo, int *graph) 83 { } 84 #endif 85 86 void 87 stack_reader_dump(struct task_struct *task, struct pt_regs *regs, 88 unsigned long *sp, const struct stacktrace_ops *ops, 89 void *data) 90 { 91 struct thread_info *context; 92 int graph = 0; 93 94 context = (struct thread_info *) 95 ((unsigned long)sp & (~(THREAD_SIZE - 1))); 96 97 while (!kstack_end(sp)) { 98 unsigned long addr = *sp++; 99 100 if (__kernel_text_address(addr)) { 101 ops->address(data, addr, 1); 102 103 print_ftrace_graph_addr(addr, data, ops, 104 context, &graph); 105 } 106 } 107 } 108 109 static int print_trace_stack(void *data, char *name) 110 { 111 printk("%s <%s> ", (char *)data, name); 112 return 0; 113 } 114 115 /* 116 * Print one address/symbol entries per line. 117 */ 118 static void print_trace_address(void *data, unsigned long addr, int reliable) 119 { 120 printk("%s", (char *)data); 121 printk_address(addr, reliable); 122 } 123 124 static const struct stacktrace_ops print_trace_ops = { 125 .stack = print_trace_stack, 126 .address = print_trace_address, 127 }; 128 129 void show_trace(struct task_struct *tsk, unsigned long *sp, 130 struct pt_regs *regs) 131 { 132 if (regs && user_mode(regs)) 133 return; 134 135 printk("\nCall trace:\n"); 136 137 unwind_stack(tsk, regs, sp, &print_trace_ops, ""); 138 139 printk("\n"); 140 141 if (!tsk) 142 tsk = current; 143 144 debug_show_held_locks(tsk); 145 } 146 147 void show_stack(struct task_struct *tsk, unsigned long *sp) 148 { 149 unsigned long stack; 150 151 if (!tsk) 152 tsk = current; 153 if (tsk == current) 154 sp = (unsigned long *)current_stack_pointer; 155 else 156 sp = (unsigned long *)tsk->thread.sp; 157 158 stack = (unsigned long)sp; 159 dump_mem("Stack: ", stack, THREAD_SIZE + 160 (unsigned long)task_stack_page(tsk)); 161 show_trace(tsk, sp, NULL); 162 } 163